I don't think SAS advertises short haul Plus as pure business class. It's more of a hybrid class between economy and plus and for what I've seen, als usually advertised as such. It has some of the advantages of the one and some of the disadvantages of the other. Price-wise it's usually in between economy and 'real' short haul business class as well. I think this is also what's causing trouble with the rest of the StarAlliance. When you need to get rebooked to another flight and it's a code share, you usually end up in the back of the bus (at least, according to my experience), as, whether it remains unclear what Plus actually is, it at least isn't business class.

I honestly don't know if I would prefer LH business class on such short hops. You get the same NEK seats anyway. And as LH Senator the chance is quite big that I get an empty seat next to me, just as I get lounge access and priority luggage. I don't think paying 3 or 4 times the price of an economy ticket is really worth sitting in front of a curtain and getting a slightly better meal served on real porcelain and cutlery.

Unfortunately, LH on short hops is usually also so much more expensive that it's unrealistic to book it, unless it's part of a long haul booking in biz.

BA is currently a big bad company that deserves severe punishment after enhancing their frequent flyer program, so we out of principle of course don't fly them nowadays.

KL actually does a fine job here. It has a clear business class and a clear economy plus class with extra legroom seats. Despite getting the same seats in biz as in eco, you at least directly know what each class means. Also the price difference for the extra legroom can be quite a good deal.